TOML ↔ JSON Converter
Convert between TOML and JSON instantly. Supports tables, arrays, inline tables, and all TOML data types — runs entirely in your browser.
Output will appear here…Frequently Asked Questions
What is TOML?
TOML (Tom's Obvious, Minimal Language) is a configuration file format designed to be easy for humans to read and write. Created by Tom Preston-Werner (GitHub co-founder), it maps unambiguously to a hash table and supports strings, integers, floats, booleans, dates, arrays, and tables. TOML aims to be simpler than YAML while more readable than JSON for config files.
How does TOML compare to JSON and YAML?
JSON is strict and widely supported but verbose and doesn't allow comments. YAML is very flexible and concise but has a complex spec with edge cases (e.g., Norway Problem). TOML sits in between: it has a simple, unambiguous spec, supports comments, and is designed specifically for config files rather than general data serialization. TOML sections (tables) map naturally to INI-style config thinking.
Where is TOML commonly used?
TOML is the standard configuration format for Rust projects (Cargo.toml), Python packaging (pyproject.toml), and Hugo static sites. It is also used in tools like uv (Python package manager), Ruff, and many other developer tools that prefer explicit, readable configuration over YAML's flexibility.
Is my data private?
Yes. All parsing and conversion happens entirely in your browser using the smol-toml library. No data is sent to any server, logged, or stored. You can safely paste your Cargo.toml, pyproject.toml, or other configuration files.